linux-stable/tools
Josh Poimboeuf 53fb6e990d objtool: Fix infinite loop in for_offset_range()
Randy reported that objtool got stuck in an infinite loop when
processing drivers/i2c/busses/i2c-parport.o.  It was caused by the
following code:

  00000000000001fd <line_set>:
   1fd:	48 b8 00 00 00 00 00	movabs $0x0,%rax
   204:	00 00 00
			1ff: R_X86_64_64	.rodata-0x8
   207:	41 55                	push   %r13
   209:	41 89 f5             	mov    %esi,%r13d
   20c:	41 54                	push   %r12
   20e:	49 89 fc             	mov    %rdi,%r12
   211:	55                   	push   %rbp
   212:	48 89 d5             	mov    %rdx,%rbp
   215:	53                   	push   %rbx
   216:	0f b6 5a 01          	movzbl 0x1(%rdx),%ebx
   21a:	48 8d 34 dd 00 00 00 	lea    0x0(,%rbx,8),%rsi
   221:	00
			21e: R_X86_64_32S	.rodata
   222:	48 89 f1             	mov    %rsi,%rcx
   225:	48 29 c1             	sub    %rax,%rcx

find_jump_table() saw the .rodata reference and tried to find a jump
table associated with it (though there wasn't one).  The -0x8 rela
addend is unusual.  It caused find_jump_table() to send a negative
table_offset (unsigned 0xfffffffffffffff8) to find_rela_by_dest().

The negative offset should have been harmless, but it actually threw
for_offset_range() for a loop... literally.  When the mask value got
incremented past the end value, it also wrapped to zero, causing the
loop exit condition to remain true forever.

Prevent this scenario from happening by ensuring the incremented value
is always >= the starting value.

Fixes: 74b873e49d ("objtool: Optimize find_rela_by_dest_range()")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Julien Thierry <jthierry@redhat.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/02b719674b031800b61e33c30b2e823183627c19.1587842122.git.jpoimboe@redhat.com
2020-04-26 09:28:14 +02:00
..
accounting SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
arch tools arch x86: Sync asm/cpufeatures.h with the kernel sources 2020-04-14 09:08:23 -03:00
bootconfig New tracing features: 2020-04-05 10:36:18 -07:00
bpf tools/runqslower: Ensure own vmlinux.h is picked up first 2020-04-24 17:45:20 -07:00
build tools/build: tweak unused value workaround 2020-04-21 11:11:55 -07:00
cgroup .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
debugging
edid tools/edid: Move EDID data sets from Documentation/ 2020-02-19 04:10:32 -07:00
firewire
firmware
gpio This is the bulk of GPIO development for the v5.7 kernel cycle. 2020-04-04 10:27:00 -07:00
hv
iio .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-24 19:17:30 -07:00
io_uring
kvm/kvm_stat tools/kvm_stat: add command line switch '-c' to log in csv format 2020-03-23 15:44:21 -04:00
laptop change email address for Pali Rohár 2020-04-10 15:36:22 -07:00
leds .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
lib libbpf: Only check mode flags in get_xdp_id 2020-04-22 22:07:22 -07:00
memory-model .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
nfsd
objtool objtool: Fix infinite loop in for_offset_range() 2020-04-26 09:28:14 +02:00
pci tools: PCI: Add 'e' to clear IRQ 2020-04-02 17:57:10 +01:00
pcmcia .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
perf tools headers: Synchronize linux/bits.h with the kernel sources 2020-04-14 11:40:05 -03:00
power pm-graph v5.6 2020-04-20 10:37:02 +02:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-03-25 18:58:11 -07:00
spi SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-24 19:17:30 -07:00
thermal/tmon - Convert tsens configuration DT binding to yaml (Rajeshwari) 2020-04-07 20:00:16 -07:00
time
usb .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
virtio tools/virtio: make asm/barrier.h self contained 2020-04-17 06:05:29 -04:00
vm tools/vm: fix cross-compile build 2020-04-21 11:11:56 -07:00
wmi
Makefile